列车动荷载作用下隧道沉降研究

Study on Tunnel Settlement under Train Dynamic Load

土地资源日益宝贵,为了节省地表资源,地下高铁隧道成为一种趋势,高速铁路荷载引起的隧道下部土体的沉降问题受到广泛关注。本文利用ABAQUS有限元建模软件模拟现场实际工况,二次开发DLOAD子程序实现列车动荷载,分析地表和隧道下监测点的沉降,探究沉降沿地层的传递规律,结合长期沉降变形模型预测该线路在未来运营期内所能达到的沉降值。研究结果表明运营前期,列车荷载作用下导致周围土压力大于上覆土压力,隧道轴向两侧上方的地表约40 m至60 m处会产生一定的隆起,土体在列车荷载加载过程中的沉降值要是稳定值的1.2~2倍左右,运营初期,土体沉降量相对较大,随着运营时间的增加,土体沉降量逐渐减小。

Land resources are becoming more and more valuable, in order to save surface resources, underground high-speed rail tunnels have become a trend, and the settlement problem of the lower soil of the tunnel caused by the load of high-speed railway has attracted widespread attention. In this paper, ABAQUS finite element modeling software is used to simulate the actual working conditions on site, and the DLOAD subprogram is developed to realize the dynamic load of the train, analyze the settlement of the monitoring points under the surface and tunnel, explore the transfer law of settlement along the formation, and predict the settlement value of the line during the future operation period based on the long-term settlement deformation model. The results show that in the early stage of operation, the surrounding earth pressure is greater than the overlying earth pressure under the action of train load, and a certain uplift will occur at about 40 m to 60 m above the surface of the tunnel on both sides of the axial direction, and the settlement value of the soil in the train load loading process is about 1.2~2 times the stable value, and the soil settlement is relatively large in the early stage of operation, and the soil settlement gradually decreases with the increase of operation time.